@inproceedings{GoemmelKobNiendorfetal.2009, author = {G{\"o}mmel, Andreas and Kob, Malte and Niendorf, Thoralf and Butenweg, Christoph}, title = {An approach for numerical calculation of glottal flow during glottal closure}, series = {Proceedings / NAG/DAGA 2009, International Conference on Acoustics : Rotterdam, 23 - 26 March 2009 ; [including the 35th German Annual Conference on Acoustics (DAGA)] / [organisers: Acoustical Society of the Netherlands (NAG); German Acoustical Society (DEGA) ...]. Ed. by Marinus M. Boone}, booktitle = {Proceedings / NAG/DAGA 2009, International Conference on Acoustics : Rotterdam, 23 - 26 March 2009 ; [including the 35th German Annual Conference on Acoustics (DAGA)] / [organisers: Acoustical Society of the Netherlands (NAG); German Acoustical Society (DEGA) ...]. Ed. by Marinus M. Boone}, publisher = {DEGA}, address = {Berlin}, organization = {NAG DAGA <2009, Rotterdam>}, isbn = {978-3-9808659-6-8}, pages = {1722 -- 1725}, year = {2009}, language = {en} } @article{BeckerFrauenrathHezeletal.2010, author = {Becker, Meike and Frauenrath, Tobias and Hezel, Fabian and Krombach, Gabriele A. and Kremer, Ute and Koppers, Benedikt and Butenweg, Christoph and Goemmel, Andreas and Utting, Jane F. and Schulz-Menger, Jeanette and Niendorf, Thoralf}, title = {Comparison of left ventricular function assessment using phonocardiogram- and electrocardiogram-triggered 2D SSFP CINE MR imaging at 1.5 T and 3.0 T}, series = {European Radiology}, volume = {20}, journal = {European Radiology}, publisher = {Springer}, address = {Berlin}, issn = {1432-1084 (Onlineausgabe)}, doi = {10.1007/s00330-009-1676-z}, pages = {1344 -- 1355}, year = {2010}, abstract = {Objective: As high-field cardiac MRI (CMR) becomes more widespread the propensity of ECG to interference from electromagnetic fields (EMF) and to magneto-hydrodynamic (MHD) effects increases and with it the motivation for a CMR triggering alternative. This study explores the suitability of acoustic cardiac triggering (ACT) for left ventricular (LV) function assessment in healthy subjects (n=14). Methods: Quantitative analysis of 2D CINE steady-state free precession (SSFP) images was conducted to compare ACT's performance with vector ECG (VCG). Endocardial border sharpness (EBS) was examined paralleled by quantitative LV function assessment. Results: Unlike VCG, ACT provided signal traces free of interference from EMF or MHD effects. In the case of correct Rwave recognition, VCG-triggered 2D CINE SSFP was immune to cardiac motion effects—even at 3.0 T. However, VCG-triggered 2D SSFP CINE imaging was prone to cardiac motion and EBS degradation if R-wave misregistration occurred. ACT-triggered acquisitions yielded LV parameters (end-diastolic volume (EDV), endsystolic volume (ESV), stroke volume (SV), ejection fraction (EF) and left ventricular mass (LVM)) comparable with those derived fromVCG-triggered acquisitions (1.5 T: ESVVCG=(56± 17) ml, EDVVCG=(151±32)ml, LVMVCG=(97±27) g, SVVCG=(94± 19)ml, EFVCG=(63±5)\% cf. ESVACT= (56±18) ml, EDVACT=(147±36) ml, LVMACT=(102±29) g, SVACT=(91± 22) ml, EFACT=(62±6)\%; 3.0 T: ESVVCG=(55±21) ml, EDVVCG=(151±32) ml, LVMVCG=(101±27) g, SVVCG=(96±15) ml, EFVCG=(65±7)\% cf. ESVACT=(54±20) ml, EDVACT=(146±35) ml, LVMACT= (101±30) g, SVACT=(92±17) ml, EFACT=(64±6)\%). Conclusions: ACT's intrinsic insensitivity to interference from electromagnetic fields renders}, language = {en} } @inproceedings{GoemmelFrauenrathOttenetal.2010, author = {G{\"o}mmel, Andreas and Frauenrath, Tobias and Otten, Mario and Niendorf, Thoralf and Butenweg, Christoph}, title = {In-vivo measurements of vocal fold geometry using Magnetic Resonance Imaging}, series = {Fortschritte der Akustik - DAGA 2010, 36. Jahrestagung f{\"u}r Akustik}, booktitle = {Fortschritte der Akustik - DAGA 2010, 36. Jahrestagung f{\"u}r Akustik}, editor = {M{\"o}ser, Michael and Schulte-Fortkamp, Brgitte and Ochmann, Martin}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik}, address = {Berlin}, isbn = {978-3-9808659-8-2}, year = {2010}, language = {de} } @inproceedings{FrauenrathGoemmelButenwegetal.2010, author = {Frauenrath, Tobias and G{\"o}mmel, Andreas and Butenweg, Christoph and Otten, Mario and Niendorf, Thoralf}, title = {3D mapping of vocal fold geometry during articulatory maneuvers using ultrashort echo time imaging at 3.0 T}, series = {ISMRM-ESMRMB joint annual meeting 2010, Band 4}, booktitle = {ISMRM-ESMRMB joint annual meeting 2010, Band 4}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Society of Magnetic Resonance in Medicine}, isbn = {978-1-617-82008-3}, pages = {3087}, year = {2010}, language = {en} } @inproceedings{KobGoemmelButenwegetal.2006, author = {Kob, Malte and G{\"o}mmel, Andreas and Butenweg, Christoph and Niendorf, Thoralf}, title = {Training of a combined model of larynx and vocal folds with data from MRI measurements}, series = {The 5th International Conference on Voice Physiology and Biomechanics: Variations across Cultures and Species, July 12-14, 2006, Tokyo, Japan. Proceedings}, booktitle = {The 5th International Conference on Voice Physiology and Biomechanics: Variations across Cultures and Species, July 12-14, 2006, Tokyo, Japan. Proceedings}, organization = {International Conference on Voice Physiology and Biomechanics <5, 2006, Tokyo>}, pages = {45 -- 46}, year = {2006}, language = {en} } @article{FrauenrathHezelHeinrichsetal.2009, author = {Frauenrath, Tobias and Hezel, Fabian and Heinrichs, Uwe and Kozerke, Sebastian and Utting, Jane and Kob, Malte and Butenweg, Christoph and Boesiger, Peter and Niendorf, Thoralf}, title = {Feasibility of Cardiac Gating Free of Interference With Electro-Magnetic Fields at 1.5 Tesla, 3.0 Tesla and 7.0 Tesla Using an MR-Stethoscope}, series = {Investigative Radiology}, volume = {44}, journal = {Investigative Radiology}, number = {9}, publisher = {Lippincott Williams \& Wilkins ; (via Ovid)}, address = {Philadelphia, Pa}, issn = {1536-0210 (online)}, doi = {10.1097/RLI.0b013e3181b4c15e}, pages = {539 -- 547}, year = {2009}, language = {en} } @inproceedings{GoemmelNiendorfFrauenrathetal.2010, author = {G{\"o}mmel, Andreas and Niendorf, Thoralf and Frauenrath, Tobias and Otten, Mario and Butenweg, Christoph and Kob, Malte}, title = {3D vocal fold geometry mapping using Magnetic Resonance Imaging}, series = {Fortschritte der Akustik : 36. Deutsche Jahrestagung f{\"u}r Akustik, Band 1}, booktitle = {Fortschritte der Akustik : 36. Deutsche Jahrestagung f{\"u}r Akustik, Band 1}, publisher = {Deutsche Gesellschaft f{\"u}r Akustik}, address = {Berlin}, organization = {Deutsche Jahrestagung f{\"u}r Akustik <36, 2010, Berlin>}, isbn = {978-3-9808659-8-2}, pages = {271 -- 272}, year = {2010}, language = {en} } @misc{MartinFrauenrathZerdemetal.2011, author = {Martin, Conrad Steven and Frauenrath, Tobias and Zerdem, Celal and Renz, Wolfgang and Niendorf, Thoralf}, title = {Evaluation of Magneto Alert Sensor (MALSE) to Improve MR Safety by Decreasing the Incidence of Ferromagnetic Projectile Accidents}, series = {2011 ISMRM Annual Meeting Proceedings}, journal = {2011 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2011}, abstract = {The magnetic forces of fringe magnetic fields of MR systems on ferromagnetic components can impose a severe patient, occupational health and safety hazard. MRI accidents are listed as number 9 of the top 10 risks in modern medicine. With the advent of ultrahigh field MR systems including passively shielded magnet versions, this risk, commonly known as the missile or projectile effect is even more pronounced. A strategy employing magnetic field sensors which can be attached to ferromagnetic objects that are commonly used in a clinical environment is conceptually appealing for the pursuit of reducing the risk of ferromagnetic projectile accidents.}, language = {en} } @article{vonKnobelsdorfBrenkenhoffFrauenrathProthmannetal.2010, author = {von Knobelsdorf-Brenkenhoff, Florian and Frauenrath, Tobias and Prothmann, Marcel and Dieringer, Matthias A. and Hezel, Fabian and Renz, Wolfgang and Kretschel, Kerstin and Niendorf, Thoralf and Schulz-Menger, Jeanette}, title = {Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla—a pilot study}, volume = {20}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {0938-7994}, doi = {10.1007/s00330-010-1888-2}, pages = {2844 -- 2852}, year = {2010}, abstract = {Objectives Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T. Methods A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated. Results All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm. Conclusions This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T.}, language = {en} } @misc{LindelGreiserWaxmanetal.2012, author = {Lindel, Tomasz Dawid and Greiser, Andreas and Waxman, Patrick and Dietterle, Martin and Seifert, Frank and Fontius, Ulrich and Renz, Wolfgang and Dieringer, Matthias A. and Frauenrath, Tobias and Schulz-Menger, Jeanette and Niendorf, Thoralf and Ittermann, Bernd}, title = {Cardiac CINE MRI at 7 T using a transmit array}, series = {2012 ISMRM Annual Meeting Proceedings}, journal = {2012 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2012}, abstract = {With its need for high SNR and short acquisition times, Cardiac MRI (CMR) is an intriguing target application for ultrahigh field MRI. Due to the sheer size of the upper torso, however, the known RF issues of 7T MRI are also most prominent in CMR. Recent years brought substantial progress but the full potential of the ultrahigh field for CMR is yet to be exploited. Parallel transmission (pTx) is a promising approach in this context and several groups have already reported B1 shimming for 7T CMR. In such a static pTx application amplitudes and phases of all Tx channels are adjusted individually but otherwise imaging techniques established in current clinical practice 1.5 T and 3 T are applied. More advanced forms of pTx as spatially selective excitation (SSE) using Transmit SENSE promise additional benefits like faster imaging with reduced fields of view or improved SAR control. SSE requires the full dynamic capabilities of pTx, however, and for the majority of today's implemented pTx hardware the internal synchronization of the Tx array does not easily permit external triggering as needed for CMR. Here we report a software solution to this problem and demonstrate the feasibility of CINE CMR at 7 T using a Tx array.}, language = {en} }